What is infundibulum of heart?

The infundibulum of the heart is a funnel-shaped structure located at the upper part of the right ventricle, adjacent to the pulmonary valve. It is also called the conus arteriosus.

The infundibulum is rich in smooth muscle fibers and is responsible for contracting and relaxing to regulate the flow of blood from the right ventricle into the pulmonary artery.

Its muscular wall contains the semilunar pulmonary valve, which opens and closes to allow blood to flow from the right ventricle into the pulmonary artery during systole and prevent backflow during diastole.

The infundibulum is also a common site for the development of congenital heart defects such as tetralogy of Fallot, which is characterized by four cardiac anomalies including a ventricular septal defect, overriding aorta, pulmonary stenosis, and right ventricular hypertrophy.